Xi vs Xixian

Xi

name

  • A river in China, the western tributary of the Pearl. 

  • A county of Linfen, Shanxi, China. 

  • Xi Jinping, current General Secretary of the Chinese Communist Party (2012–present). 

  • A surname from Chinese 

noun

  • Capital Greek letter Ξ (X) 

Xixian

How often have the words Xi and Xixian occurred in a corpus of books? (source: Google Ngram Viewer )